diff --git a/src/erpbrasil/assinatura/assinatura.py b/src/erpbrasil/assinatura/assinatura.py
index 0d2aef1..0327287 100644
--- a/src/erpbrasil/assinatura/assinatura.py
+++ b/src/erpbrasil/assinatura/assinatura.py
@@ -4,9 +4,6 @@
 from cryptography.hazmat.primitives import hashes
 from cryptography.hazmat.primitives.asymmetric import padding
 from lxml import etree
-from Crypto.PublicKey import RSA
-from Crypto.Hash import SHA
-from Crypto.Signature import PKCS1_v1_5
 from hashlib import sha1
 
 
@@ -146,15 +143,6 @@ def assina_pdf(self, arquivo, dados_assinatura, algoritmo='sha256'):
             algomd=algoritmo
         )
 
-    def assina_tag(self, message):
-        privateKeyContent = (self.certificado._chave).decode('utf-8')
-        message = message.encode('utf-8')
-        message = SHA.new(message)
-        rsaKey = RSA.importKey(privateKeyContent)
-        signer = PKCS1_v1_5.new(rsaKey)
-        signature = signer.sign(message)
-        return b64encode(signature).decode()
-
     def verificar_assinatura_string(self, message, signature):
         public_key = self.certificado.key.public_key()
         return public_key.verify(